People are inherently afraid of snakes, often because of the stealthy manner in which they live and move around, but more often because many snakes have a deadly bite. Many people cannot differentiate between a venomous snake and a non-venomous snake, and thus are afraid of all snakes.
The Crotalid family (pit vipers) of snakes is the most prominent venomous snake in North America and is responsible for most of the human snake bite fatalities. The Crotalid family of snakes includes rattle snakes, copper heads and water moccasins. This type of venomous snake locomotes with their heads low to the ground and are seldom aboralistic, i.e., climb trees or the like. Most snakes have very poor vision and rely on Jacobson organs (smell), heat sensors and vibrations to track and catch prey and avoid predators. It is desirable to create an area of ground where crawling snakes are blocked from reaching.